Safety Towing Tips & TerminologyThings that you should be familiar with before & while towing a trailer

Gross Vehicle Weight (GVW): is not a rating, it is the actual maximum weight of the tow vehicle when it is fully loaded including all options, cargo, personal belongings, food, water and LP gas.

Gross Combined Weight Rating (GCWR): is the maximum permissible combined weight of the tow vehicle and the trailer together when they are fully loaded for travel.

Unlaiden / Unloaded Vehicle Weight or Dry Weight (UVW) or (DW): is the actual weight of the tow vehicle or trailer as built at the factory. The UVW does not include passengers, cargo, dealer installed options, personal belongings, water, or LP gas.

Vehicle Tow Rating: Make sure your tow vehicle is capable of towing the intended trailer or accessory. The trailer or accessory and the vehicle work together in determining the maximum capacity. In no case should the GTW or TW exceed the towing capacity of your vehicle, your trailer or your accessory. Find this information in the vehicle owners manual or www.trailerlife.com, look under “tow ratings”.

Gross Vehicle Weight Rating (GVWR): Is the maximum weight of the fully loaded trailer, as published on the Certification / VIN label. Actual weight determined by weighing trailer on a public scale, without being attached to the towing vehicle.

Hitch Weight: The downward force exerted on the hitch ball by the trailer coupler.

Gross Axle Weight Rating (GAWR): The maximum weight that any axle can support, as published on the Certification / VIN label on the front left side of the trailer. Actual weight determined by weighing each axle on a public scale, with the trailer attached to the towing vehicle.

Both tire and VIN certification labels are permanently attached to the trailer near the left front corner or on the tongue of the trailer.

Both Tire And VIN Certification Labels are permanently attached to your tow vehicle on the drivers door panel or on the column behind drivers door. See owners manual for further details or specifications.

Understanding Tires:

Example: ST205/75R15

ST - Trailer Tires only

LT - Light Trucks or Trailers

P - Passenger Tires

Next 3 Digits - give the width in millimeters of the tire from sidewall edge to sidewall edge

Next 2 Digits - give the aspect ratio, the tires ratio of height to width

R - Radials

D - Bias Ply

Last 2 Digits - gives the wheel or rim diameter in inches

Bias ply tire: A pneumatic tire in which the ply cords that extend to the beads are laid at alternate angles substantially less than 90 degrees to the centerline of the tread.

Example - ST205/75D15

Radial ply tire: A pneumatic tire in which the ply cords that extend to the beads are laid at substantially 90 degrees to the centerline of the tread.

Example – ST205/75R15

Load rating: The maximum load that a tire is rated to carry for a given inflation pressure.

Tire Ply: Is the number of layers of rubber coated fabric in the tire.

Load Range: (Load range = 2ply/ Letter) Letters are used to identify a given size tire with its load and inflation limits, when used in a specific type of service.

Recommended inflation pressure is provided by the vehicle manufacturer on the tire sidewall and on the Certification / VIN tag, which is usually located at the front left side of the trailer.

Hitch Terminology:

GTW = Gross Trailer Weight - the weight of the trailer fully loaded TW=Tongue Weight-The downward force that is exerted on the hitch ball by the coupler. The tongue weight will vary depending on where the load ia positioned in relationship to the trailer axle(s).WC = Weight Carrying - The total weight of both the trailer and cargo inside. Never exceed the weight capacity of your trailer hitch. This applies to loads without a weight distribution systemWD = Weight Distributing - Used to balance the weight of the cargo between the front and rear wheels throughout the trailer, alowing for better steering, braking, and level riding. Not to be used on class 1 or 2 receivers, or with surgebrakes.

To select the right hitch for your vehicle:

1. Check the towing capacity of you tow vehicle. 2. Determine the gross trailer weight (GTW) of your tow item. 3. Select the class of hitch rated for you vehicle.

NOTE: Never tow a trailer with a gross trailer weight greater than the vehicle manufacture's rating. It could cause damage to the vehicle's engine transmission and frame. And could void any manufacture's warranties. A higher class of hitch DOES NOT increase the vehicle's tow capacity.

Vehicle Type >>

Compact Cars

Mid-Size Cars

Full-Size CarsMini-Trucks& Vans

Full-size Trucks,Vans & SUVs

Hitch Class Rating

Class IWC GTW - Up to 2,000 lbs.WC TW - Up to 200lbs.

Light Duty

Light Duty

Light Duty

Light Duty

Class IIWC GTW - Up to 3,500 lbs.WC TW - Up to 350lbs.

Medium Duty

Medium Duty

Medium Duty

Class IIIWC GTW - Up to 5,000 lbs.WC TW - Up to 500lbs.

Heavy Duty

Heavy Duty

Class IVWC GTW - Up to 7,500 lbs.WC TW - Up to 750lbs.WD GTW - Up to 12,000 lbsWD TW - Up to 1,200 lbs

Heavy Duty

Heavy Duty

Class VWC GTW - Up to 12,000 lbs.WC TW - Up to 120lbs.WD GTW - Up to 14,000 lbsWD TW - Up to 1,400 lbs

Extra Heavy Duty

Hitch Ball:

Always be sure that the ball size & trailer coupler size are matched, and weight rating is sufficient for the trailer being towed.

Weight Distributing Hitch Systems:

“also referred to as sway bars, leveling bars, etc.” are designed to increase the capacity of the towing system when added to a Class III, IV or V trailer hitch. The idea is to distribute the load of the trailer evenly to the entire tow vehicle and trailer wheels. To accomplish this, spring bars are used to absorb load and level the trailer. This offers a more level ride, improved steering and increased braking control, all the while enhancing towing safety.

Always try to maintain the trailer coupler & vehicle hitch in a level position to help minimize fishtailing. Fishtailing refers to the erratic side to side movement of the trailer. It is important when towing a trailer whether it is a bumper pull or a gooseneck style to achieve a level position when loaded. The reason for this is that you want to have an even weight displacement on the axles. For example, if the trailer is to high in the front excessive stress may be applied to the rear axle and/or if the front of the trailer is to low the front axle may become stressed. In extreme cases this can lead to axle failure due to overloading. When hitching up to an unloaded trailer we recommend having the trailer set up slightly higher in the front to allow for settling once the trailer is loaded. Further adjustment of trailer front height may be required as load conditions change.

Cargo Placement:

Always keep your load balanced front/back & side/side as not to have too much or too little weight on the tongue. The tongue weight should never exceed 10% of the Gross Towing Weight.

Load Securement:

Make sure that all items are properly secured inside & on the trailer. The driver is responsible for anything that may separate from the trailer.

Torflex® axles are designed as a completely self-contained axle and suspension system. This trailing arm type torsion axle employs natural rubber cords supporting heat treated inner bars of solid, medium carbon steel. Press-fitted and welded to the ends of this independently floating bar are high strength steel torsion arm/spindle assemblies. These arms can be specified to a range of starting angles, which allow the designer to tailor the running height of the vehicle.

Torsion Axle

Leaf Spring axles utilize high strength steel spindles welded to high strength tubing to form an axle beam. The spindles are usually available in either a straight or drop design to help designers establish the desired frame height or ground clearance. Leaf springs are attached to the axle using u-bolts and can be positioned either under or over the tube. Use under mounted springs (underslung) to lower the frame height and over mounted springs (overslung) to raise the frame height.

Spring Axle

Ball Mounts:

The ball mount is placed inside the opening of the receiver hitch which is mounted to the vehicle. Make sure a hitch pin is properly securing the ball mount to the receiver hitch before you begin towing. Ball mounts are grouped into three (3) styles.

Style Type 1Used for vehicle and trailer equally level towing

Style Type 2Used for vehicle and trailer NOT equally level towing

Style Type 3Straight Cut

Trailer Ball:

The most important connection from the hitch to the trailer.

There are many factors that determine the correct hitch ball:

Most important is the hitch ball's gross trailer weight rating

The mounting platform must be at least 3/8" think

The hole diameter must not be more than 1/16" larger than the threaded shank

Every time you tow, check the nut and lock washer to make sure they are fastened securely

Coupler:

The component that is placed over the trailer ball to connect the vehicle to the trailer. Be sure that the coupler size matches the size of the hitch ball and that the coupler handle is securely fastened. To determine what size hitch ball you need for your application you will need to know the size of the coupler that is on the trailer. Be sure your coupler is properly adjusted to the ball you are using.

Safety chains are a requirement and should be crossed under the tongue of the trailer so that the tongue will not drop to the road if it becomes separated form the hitch. Always leave enough slack so you can turn. Never allow the safety chains to drag on the ground and never attach the chains to the bumper.